Cellulosic plastic composition



Patented ct. 12, 1943 2,331,330 FFlC-E assrsso csnLnLosic ms'rrc COMPOSITION Lucas P. Kyrides, Webster Groves, Mm, assi or to Monsanto Chemical Company, St. Louis, 0., a corporation of Delaware No Drawing. Original application June26, 1940,

Serial No. 342,443.

Divided and this application January 11, 1943, Serial No. 472,001

12 Claims. (01. 106-181) The present invention relates to plastic com-- positions of matter which contain plastic substances embodying a plurality of C-OC linkages and refers particularly to a new class of softening or plasticizing compositions for use as camphor substitutes for such plastic compositions, specifically to esters of hydroxycyclohexanones, The invention relates also to a new method of preparing esters of hydroxycyclohexanones and certain new compounds of this series.

This application is a division of my. copending application, Serial No. 342,443, filed June 26, 1940.

The principal object of the invention is to provide improved softening or plasticizing compounds for use in plastic compositions embodying a plurality of -0-0 linkages, particularly cellulose derivatives, for example, cellulose esters and ethers such as cellulose acetate, cellulose nitrate and ethyl cellulose, and polyvinyl acetal resins. Another object of the invention'is to provide a method of preparing such plasticizing compounds. These and other objects of the invention, some of which are referred to specifically hereinafter, will be apparent from this deseription.

My invention is based on the discovery that L esters of hydroxycyclohexanones are compatible to a remarkable extent with polyvinyl acetal resins and cellulose derivatives such as cellulose acetate and cellulose nitrate and that the plastic compositions resulting from such admixture are characterized by excellent stability to light, good "flexibility, high tensile strengthand fair elonsation. I have also discovered a new method of preparing esters of hydroxycyclohexanones which makes it possibletoproduce such compounds in an economical manner and in high yield.

, The acetate of 2-hydroxycyclohexanone of the formula H: mo d=o 7 H2 H-O-CCHa is an example of an ester of a hydroxycyclohexa none that is suitable for use according'to my invention. This compound was first described tems of nomenclature, as 1,2-cyclohexanolone acetate, acetate of adipoin, or simply o-cycloresponding to a keto-cyclohexanol ester in which the carbinol group has been esterifled by an acid. Throughout this specification. therefore, the compounds will be referred to as esters of a hydroirycyclohexanone and it is to be understood that the carboxyl group has been substituted in the cyclohexanone in a manner corresponding to esterification of the hydroxyl group of the hydroxycyclohexanone by an acid, although this is not actually the method by which I produce the compounds.

The benzoate of 2-hydroxycyclohexanone is also known and'was descrlbedby Kotz-et al., in Annalen, 1913,vol. 400, page 63, by Bergman and Gurth, in Annalen 1926, vol. 448, page 72 and by Wilson and Read in Journal of the Chemical Society (London), 1935, page 1273, although its melting point was given as 122 to 123 C., 87 C., and 85 to 86 C., by the respective investigators. The esters for use in my invention may be hydroxycyclohexanone esters of simple monocarboxylic aliphatic acids such as formic, acetic, propionic, butyric, valeric (pentanoic) caproic (hexanoic) heptanoic, octanoic and the like, including isomers and higher homologues therecontaining one free unesterified carboxyl group such as. monoethylphthalic, monomethylphthal ic, monobutylphthalic and monoethylsuccinic acids and esters of polycarboxylic acids containing one free unesterified carboxyl group in which the other carboxyl groups have been esterified by keto-alcohols or ether alcohols, for example, monoacetonyl phthalic acid or the monophthalyl ester of the monoethyl ether of ethylene glycol.

The esters may also be derived from monocar- .boxylic ether acids and esterified polycarboxylic ether acids containing one unesterified carboxyl group such as ethoxyacetic acid 1 f (C2H5OCH2COOH) monoethyldiglycolic acid i v and the like. In general, any acid corresponding hexanonyl acetate, none 'ofwhich names is sufilto a carboxyl-substituted hydrocarbon or ether which may have as optional substituents, chlorine, hydrocarbon radicals or carboxyl radicals esterifled by alcohols, ether" alcohols or. keto-alcohols, may be used. One or more such acid radicalsmay be substituted in the cyclohexanone nucleus. The hydroxycyclohexanone from which the compounds/can be considered to be derived may be 2-hydroxycyclohexanone, 3-hydroxycy- -clohexanone, 4-hydroxycyclohexanone, polyhydroxycyclohexanones, and homologues thereof,

although, because of ease of preparation, the mono-esters of 2-hydroxycyclohexanone are preferred. In general, the esters of hyd'roxycyprefer to Mono-esters-of Z-hydroxycyclohexanone are preferred compounds and examples of such compounds are the acetate, butyrate, hexanoate, monoethyldiglycolate, monoethylthiodiglycolate, ethoxyacetate and monoethylphthalate of 2- hydroxycyclohexanone.

General methods of preparing esters of hy-'- droxycyclohexanones have been heretofore described. The acetate of 2-hydroxycyclohexanone was prepared heretofore by reacting 2-hydroxycyclohexanone with acetic anhydride, using pyridine as a solvent and by reacting 2-bromocyclohexanone with silver acetate. The benzoate of 2-hydroxycyclohexanone was prepared heretofore by esterifying 2-hydroxycyclohexanone with benzoyl chloride in pyridine in the presence of a trace of acetic acid as a catalyst, in one case, and in the absence of acetic acid in another; and, according to another method, by oxidizingvmonobenzoyl cyclohexane-1,2-diol with potassium dichromate and sulfuric acid. None of these general methods are commercially feasible for the preparation of compounds which are to be used as camphor substitutes or to replace other plasticizers because the costs of the products made according to such methods are .too high.

The foregoing heretofore known methods involve either the initial preparation of 2-hydroxycyelohexanone, which is not simple; the use of acid chlorides, which are expensive; the use of silver bromide, which is expensive and will be partially lost and unrecovered; or the use of oxidizing procedures which require a high degree of control to produce good yields. Because of these,- and for other obvious reasons militating against the use of these general methods for the production of the compounds, I had considered using the reaction of chlorocyclohexanone or bromocyclohexanone with sodium acetate. The reaction of z-chlorocyclohexanone and 2-bromocyclohexanone with sodium acetate in glacial acetic acid was heretofore described, however, but the only product which is formed is cyclohexenone,

' according to Kdtz and Grethe, in Journal fiir praktische' Chemie, 1909, vol. 80 (New Series), pages 491 and 493 (see also Beilstein, "Handbuch der organischen Chemie, Berlin, 1932, vol. VII, pages and 51).

After unsuccessful attempts to flnd other methods 'of making esters of hydroxycyclohexanones, in a commercially feasible manner, I tried the reaction of 2-chlorocyclohexanone with anhydrous sodium acetate in glacialacetic acid, and found, contrary-to expectations based on the reports of others, that the reaction yielded the acetate of hy'droxycyclohexanone in good yield. This general reaction is the basis of my preferred method or making acid esters of hydroxycyclohexanones and is illustrated in theexampies which follow:

Exanrm: I.Acetate of Z-hydroxycucloheranone The starting material for this synthesis is 2- chlorocyclohexanone which can be prepared by the direct chlorination of cyclohexanone. The

chlorination may be conducted in a diluent such as benzene and is preferably conducted in the presence of marble or a similar material which will absorb or neutralize the hydrogen chloride formed in the reaction. To restrict the chlorination to a monochlorinated derivative, the cyclohexanone is underchlorinated, that is, the chlorination is conducted to an extent corresponding to the conversion of about 33% but less than about and preferably not more than 67% to the monochlorinated cyclohexanone. From such a reaction mixture the chlorocyclohexanone, having a boiling point of approximately to 108 C. at a pressure of 26 mm., can be separated by fractional distillation.

A mixture of 85 grams of anhydrous sodium acetate (about 1.04 mol) suspended in '70 grams of glacial acetic acid (about 1.17 mol) is placed in a flask provided with a stirrer and reflux condenser. The mixture is heated to about 100 C., and grams of 2-chlorocyclohexanone (about 0.94 mol) is added thereto in small portions by means of a dropping funnel while a gentle reflux is maintained. The heating is continued at such a temperature as to maintain the gentle reflux for about 12 hours. The reaction mixture is then cooled and diluted with sufficient water to dissolve the salts. Benzene is then added to take up the organic substances and thereafter the aqueous and benzene layers are separated. The benzene layer is washed with water and then with dilute sodium carbonate solution and finally with water until the washings ar approximately neutral. The benzene solution is then fractionated, the product being recovered in vacuum. The acetate of 2-hydroxycyclohexanone has a boiling point of about 108 to 110 C. at a pressure of 10 mm., a-boiling point of about 112 C. at 12 mm., and about 235 C. at atmospheric pressure.

Its melting point is 40 to 42 C. The yield was 102 grams of ester, which is approximately 69% of the theoretical yield based on the 2-chlorocyclohexanone used in the reaction.

Instead of using pure 2-chlorocyclohexanone in the foregoing preparation, an underchlorinated cyclohexanone reaction mixture from which reacted and unreacted marble or other hydrogenchloride-absorbent has been removed, may be used.

EXAMPLE- II.But1/mte of Z-hydroxycyclohezanone .Into a three-necked flask, provided with a reflux condenser, stirrer and dropping funnel, is placed 148 grams of 99% butyric acid (about 1.66 mols). Sodium hydroxide pellets are then added slowly while the mixture is agitated, until 30.5 grams of sodium hydroxide (about 0.76 mol) has been added. The mixture is then heated while stirring until all thesodium hydroxide is dissolved, and the water formed in the reaction is then distilled oif in partial vacuum so as to leave anhydrous sodium butyrate and butyric acid in the flask.

To the anhydrous sodium butyrate-butyric acid mixture (about 0.76 mol sodium butyrate and 0.89 mol butyric acid), thus obtained is then added slowly, through the dropping funnel, 84 grams of 2-chlorocyclohexanone (about 0.63 mol) while maintaining a reaction temperature of about 150 C. The reaction mixture is then maintained at a gentle reflux, the temperature being about to C., for a period of about 10 hours.

The product is recovered as in Example 1. The benzene layer may be dried with calcium chloride, sodium spliate or other drying agent, ii desired, prior to distillation. The butyrate of 2- hydroxycycloh'exanone has a boiling point of about 125 to 130 C. at a pressure of 8 mm. and a boiling point of about 260 C. at atmospheric pressure. The yield was approximately 101 grams, which is' 86.5% of the theoreticalyield from the 2-chlorocyclohexanone used.

Examrrr III.n-He:ranoate of Z-hydrorycyclohexanone The hexanoic acid ester of 2-hydroxycyclohexanone isprepared by substituting 116 grams of n-hexanoic acid (about 1 mol) for the butyric .acid, 20 grams of sodium hydroxide pellets (about 0.5 mol) for the 30.5- grams of such pellets, and 66 grams of 2-chlorocyclohexanone (about 0.5 mol) for the 84 grams of this compound in Example II, and the procedure therein described is followed. The refluxing temperature is about 155 C. and refluxing is continued for about 4 hours instead of hours.

The n-hexanoate of 2-hydroxycyclohexanone has a boiling point of 140.to 148 C. at a pressure of 7 mm. and a boiling point of 285 to 287 C. at atmospheric pressure and is obtained in a yield of about 91 grams, which is 86% of the "theoretical yield based on the Z-chlorocyclohexanone used.

EXAMPLE IV.--Ethylphthalyl ester of Z-hydroxycyclohexanone mols). The mixture is heated to reflux temperature (about 81 C.) while stirring, and is refluxed gently for about one-half hour at this temperature. The mixture containing monoethylphthalic acid is then allowed to cool to about 75 C., and 41.7 grams of anhydrous (99.5%) potassium carbonate (about 0.3011101) is added slowly with stirring over the course of onehalf hour while the temperature is maintained at 65 to 75 C. The mixture is thereafter heatedat a gentle refluxing temperature for an additional one-half hour. The resulting solution of potassium monoethylphthalate is not entirely clear. To this solution is then added 66.5 grams of z-chlorocyclohexanone (about 0.5 mol) in small portions (about 10 minutes being required for the addition). After this addition the mixture is refluxed for about 25 hours.

From the reaction mixture the monoethylphthalyl ester of 2-hydroxycyclohexanone may be recovered as follows: The excess alcohol is removed by evaporation in vacuum to a maximum temperature of 130 C. or thereabout at a pressure of 20 mm. The mixture is then cooled and washed with 250 cc. of warm water (60 to 2-hydroxycyclohexanone, having a melting point of 66 to 66.5 0., is about 107.4 grams, which corresponds to 74.0% of the theoretical based on' the 0.5 mol oi chlorocyclohexanone used. On recrystallization from 50% ethyl alcohol, the pugified product had a melting point of 67 to 67. C.

According to the general method of preparing esters of hydroxycyclohexanones illustrated in the foregoing examples, the procedure consists essentially in reacting a chlorinated cyclohexanone or a chlorination mixture containing unreacted cyclohexanone with a sodium or potassium salt of the acid corresponding to the desired esterin the presenceof the free acid, under substantially anhydrous conditions. Other alkalimetal salts of the acid may be used, if desired. Isomeric chlorocyclohexanones may be used to prepare the corresponding derivatives although the invention is specifically directed to the use of Z-chlorocyclohexanone, which is the principal product obtained on direct chlorination of cyclohexanone. Brominated or iodinated cyclohexanones may be used instead of the chlorinated derivatives, in which case the reaction is faster but not as well a'dapted'to commercial utilization.

70 C'.) and is thereafter stirred into 250 cc. of

water containing about 15 grams of sodium carbonate or more, if required to maintain the mix 500 cc. of distillate is collected. The distillatemay be washed and treated with dilute alkaline solutions for further purification if desired. The

crystalline material removed and washed with.

tives such as cellulose esters and ethers.

Other conventional methods of purification may be used for recovery of the ester of the hydroxycyclohexanone as is obvious.

In my method of preparing esters of hydroxycyclohexanones I. use approximately stoichiometrical quantities of the alkali-metal salt of the acid and the halogenated cyclohexanone, although an excess of about 50% or somewhat more of the alkali-metal salt of the acid may be used to drive the reaction with the halogenated chlorocyclohexanone toward completion. However, I preferto avoid the use of free acid, as in the preparation of the ethylphthalyl ester of hydroxycyclohexanone (Example IV), or use it onlyin an amount corresponding stoichiometrically to'approximately not more than that of the-alkali-metal salt. The reaction mixture is heated at reflux temperatures .for periods of one.

hour or longer, generally from four to thirty .hours', as shown in the examples; or, if large batches or somewhat less reactive substances are used, the reaction period may be even longer than this.

The esters of hydroxycyclohexanones are powerful solvents and plasticizers for cellulose esters such as cellulose nitrate and acetate. In respect to their action on cellulose nitrate they resemble camphor very closely and as plasticizers for cellulose nitrate are superlative camphor substitutes possessing properties not possessed by camphor. In general, the plasticizers are compatible with plastic substances embodying a plurality of C-OC linkages astypified by polyvinyl acetal resins and cellulose deriva- Plastic compositions modified by these plasticizers are illustrated in the examples which follow:

' oil is then cooled to 10 to 15 C. and the solid EXAMPLE A;Nitrocellulose containing the tate of z hydroxycyclohexanone Nitrocellulose was dissolved in a 50-50' mixture of butyl acetate and toluene and to portions of said solution was added the acetate of Z-hydroxycyclohexanone in varying proportions. The solution was then cast by pouring out the solution on glass plates and allowing the solvent to 'aceevaporate. The films in all cases were approximately 0.0015 inch in thickness. The results obtained by subjecting films containing various proportions of the plasticizer to tests were as given in the following table. The parts of plasticizers represent parts by weight of plasticizer per 100 parts by weight of nitrocellulose. Results with nitrocellulose films plasticized with camphor are given for comparison.

Parts Tensile Elonga- Schopper ag Light plasticizcr strength tion folds g fastness Kg./cm. Per cent Per cent 550 5 40 100 Fair. 460 5 l8 4' D0. 394 7 17 55 Do. 280 4 14 58 Do.

25 camphor. 460 5 27 89 Do. 50 camphor. 380 6 22 84 Do. 75 camphor. 328 4 14 96 Do. 100 cam phcrv 256 6 i2 170 The acetate of 2-hydroxycyclohexanone is compatible up to 100 parts in nitrocellulose but such films are tacky and soft, indicating high solvent power. The plasticizer is more permanent than camphor in nitrocellulose.

Exsxru: B.Cellul0se acetate plasticized with the acetate 0! Z-hydrozwcyclohezranone Cellulose acetate films plasticized with the acetate of z-hydroxycyclohexanone were cast as in Example A. The cellulose acetate used was Hercules PM-6 and the solvent for casting was acetone. The properties of such films and comparison with cellulose acetate films plasticizecl with The acetate of Z-hydroxycyclohexanone is compatible up to 100 parts in cellulose acetate but at such high ratio the films are tacky and soft indicating high solvent power.

EXAMPLE D.-Cellulose acetate plasticized with the butyrate of Z-hydroxycyclohezranone 1 Moisture Parts Tensile Elonga- Schcppcr "new Light plastlcizer strength tion folds g fastness Per cent Per cent 6 30 100 Excellent. 30 28 97 D0. 5 75 91 D0. 10 49 79 D0. 29 87 D0.

The butyrate of 2-hydroxycyclohexanone is compatible in cellulose acetate up to 100 parts and the film is firm and non-tacky.

EXAMPLE E.-Nitrocellulose plasticized with the hexanoate of Z-hydroxycyclohexanone Cast films of nitrocellulose plasticized with the hexanoate of Z-hydroxycyclohexanone were made as in Example A. The properties of such films, and comparison films of nitrocellulose plasticized with camphor were as follows:

The hexanoate of Z-hydroxycyclohexanone is compatible in nitrocelluloseup to '75 parts but the films are soft and tacky, indicating high solvent power.

ExAuPLr: F.C'ellulose acetate plasticized with the hezanoate of Z-hydroxycyclohezanone Cast films of cellulose acetate (Eastman A-l3) plasticized with the hexanoate of 2-hydroxycyclohexanone were made as in Example B. The properties of such films and comparison films of the same cellulose acetate plasticized with camphor were as follows:

55 EXAMPLE C.--Nztrocellulose plasticized with the Tensile E1911, schopper Mo i ture Light butvrate of Z-hvdrorvcyclohexanone plasticim' strength tion folds' 3 g? {mm Cast films of nitrocellulose plasticized with the butyrate of Z-hydroxycyclohexanone were made 0 gs 1; m Ti, Excellent as in Example A. The properties of such films x 1 39 14 Do. were as follows: 300 22' g 1% 153' a act I 41 10s 54 D01 Moisture 25-camphor- 100 15 12 85 Good P Tensile Elam Bchopper Light 50 h plsstic'ller strength tion folds fastness I '75 333 81 550 28 m plz 83 D0.

Kg ./c;l rang B Per ce l pm The hexano'ateof 2-hydroxycyclohexanone is w 6 25 compatible with cellulose acetate up to 100 parts. 200 1 19 n =1) V394 5 1,8 a Exmm: G.N2trocellulose plasticized with the 'me butyrate of -hydrox ycyclohexanone is a compatible in nitrocellulose up to 100 parts but at such high concentrations the film is soft and tacky. indicotinz high solvent power.

Cast aims of nitrocellulose plasticized with varying proportions of the monoethyl phthalate of Z-hydroxycyclohexanone were made as in Exmofloethulphthalate of Z-hydroxycycloheza- In nitrocellulose more than 100 parts ofthe ethylphthalyl ester of 2-hydroxycyclohexanone is compatible but at such high concentrations the films are soft and tacky, indicating high solvent power.

Examnn H.Cellulose acetate plasticized with the monoethylphthalate of Z-hydrozcycyclohezamme Cast films of cellulose acetate (Eastman A-13) plasticized with the monoethylphthalate of 2- hydroxycyclohexanone were made as in Example B. The properties of such films were as follows: Y

I Parts Tensile Elonga- Schopper iggi Light plasticizer strength tion. fol Pbmty iestness KqJcm 1 Per cent Per cent 863 12 100 Excellent. 25 640 ll 19 58 0. 50 590 13 12 37 Good.

In the particular cellulose acetate the monoethyl phthalate of Z-hydrbxycyclohexanone is compatible at 50 parts but incompatible at '75 parts,

EXAMPLE I.PoZyuin1/Z acetal resin plasticized with the butyrate of Z-hydrozcycyclohexanone Into 100 parts of Butvar, apolyvinyl acetal resin resulting from the condensation of butyraldehyde with a partially hydrolyzed polyvinyl ester, was incorporated by hot milling 50 parts by weight of the butyrate or Z-hydroxycyclohexanone. Films of approximately 0.020 inch thickness were then pressed from the plasticized composition.

The film thus obtained was transparent, showed excellent elasticity and recovery and was rubbery, possessing the property known in the rubber industry as nerve. The film had good adhesion to glass and to Cellophane. It withstood 80 bends through an angle of 180 and return at a temperature of 20 F. before breaking. In general, rubbery properties of the sheets are pronounced when 30 to '70 parts of the plasticlzer are present in 100 parts of the resin.

EXAMPLE J.Polyvinyl acetal resin plasticized with the hezanoate of 2hydroxycyclohe:canone A film was made as in Example I using 50 parts by weight of the hexanoate of Z-hydroxycyclohexanone. This film had substantially the same properties as those observed in the film-of Ex-. ample I but had better adhesion to glass and Cellophane and withstood 100.bends through an angle of 180 and return at a temperature of -20 F. before breaking.

aldehyde and mixtures thereof, are similarly mod ified in characteristics by esters of hydroxycyclo- 5 ers for cellulose derivatives such as cellulose es- Other polyvinyl acetal resins such as conden-p ters and ethers and for polyvinyl acetal resins and, in general, for plastic substances embodying a plurality of C-OC linkages. They impart a desirable combination of properties to plastics with which they are incorporated.

.Esters of hydroxycyclohexanones may be used in combination with other conventional plasticizers such as camphor, dimethyl phthalate, diethyl phthalate, dibutyl 'phthalate, diamyl phthalate, tributyl phosphate, triphenyl phosphate, tricresyl phosphates and toluene-sulfonamide-type plasticizers to provide films of intermediate properties.

The invention hasbeen described with reference tov films of plastic compositions but the pies ticizers may be used in combination with cellulose .esters and ethers and polyvinyl acetal resins in liquid coating compositions and in molded and cast plastics.

Transparent films of cellulose derivatives and polyvinyl acetal resin compositions plasticized with esters of hydroxycyclohexanones are especially desirable interlayers for safety glass.

Reference is made to my copending divisional application, Serial Number 390,108, filed April 24,

194i, in which is claimed subject matter that is disclosed but not claimed herein.

Inasmuch as the foregoing specification comprises preferred embodiments of the invention it is to be understood that these are-merely illustrative and that modifications and variations may be made therein in accordance with the principles herein set forth'without departing substantially from the invention which is defined and limited only by the appended claims.

' I claim:

1. A plastic composition comprising a plastic substance embodying a plurality of (3 0-0 linkages and selected from the group consisting of cellulose esters and cellulose ethers, and having as a modifier therefor a carboxylic acid ester of a hydroxycyclohexanone.

2. A plastic composition comprising a plastic substance embodying a plurality of C-O-C linkages and selected from the group consisting of cellulose esters and cellulose ethers, and having as a modifier therefor-an organic ester of 2-. hydroxycyclohexanone.

3. A plastic interlayer film for safety glass formed of a plastic composition comprising a plastic substance embodying a plurality of C-O--C linkages and selected from the group consisting of cellulose esters and cellulose ethers, and having as a modifier therefor an organic ester of hydroxycyclohexanone.

4. A plastic composition comprising a plastic substance embodying a plurality oi C-O-C linkages and selected from the group consisting of cellulose esters and'cellulose ethers, and having-v as a modifier therefor an aliphatic ester of 2-hydroxycyclohexanone.

5. A plastic composition comprising a plastic substance embodying a plurality of CO-'-C linkages and selected from the group consisting of cellulose esters and cellulose ethers, and have ing as a'modifier therefor a monoalkylphthalyl ing as a modifier therefor monoethylphthalyl ester of 2-hydroxycyclohexanone.

7. A plastic composition comprising a plastic substance embodying a plurality of 0-0-0.

10. A plastic composition comprising nitrocellulose and the acetate oi Z-hydroxycyclohexanone.

11. A plastic composition comprising a. plastic substance embodying a plurality of CO-C linkages and selected from the group consisting of cellulose esters and cellulose ethers, and having as a modifier therefor the hexanoate of 2- hydroxycyclohexanone.

12. A plastic composition comprising a plastic substance embodying a. plurality of C-OC linkages and selected from the group consisting of cellulose esters and cellulose ethers. and having as a modifier therefor a carbomlic acid ester 9. A plastic composition comprising cellulose 15 of 2-hydroxycyclohexanone.

acetate and an organic ester of 2-hydromyclohexanone.

LUCAS P. KYRIDES. 

